Speedometer drive-gear.



E. A. LARSON. SPEEDOMETER DRIVGEAR. APPLICATION FILED IUNE23, [913.

lutcnted NOV. 23, 1915.

EDWARD LARSON, OF CHICAGO, ILLNOIS, ASSIGNOR T0 STEWRT-WARNER SPEED- 0MEJER CORPORATION, 013 CHICAGO, IL LINOIS, A CORPORATION OF VIRGIN'IA.

SPEEDOMETER DRIVE-GEAR.

Speciflcation of Letters Patent.

Patented Nov. 23, rare.

Application filed J une 28, 1913. Serial No. 775,186.

'of Illinois, have invented new and useful ImproVements in Speedometer Drive-Gens, of which the followmg is a spec1ficat1on, reference being had to the accompanying drawings, forming a part thereof.

The purpose of th s mvention is to provide a simple and efiicient gearmg for transmitting rotation 'from the pi0peller shaft of ings as more a motor driven ehicle' to* a speedometer mounted' in any convenient p0s1t1on upon the vehicle, preferably on the dash-board.

. The invention COIISlStS oithe features and elements described and shwn in the draw, particularly indicated by the claims.

In the drawings:Figure 1 is a partial plan view of' an automobile chassis showing the drive gear installed thereon. Fig. 2 1s a detail section taken as indicated at hne 22 on Fig. 1. Fig. 3 is a detail section 'takeg 25 as'indicated at line 33 on Fig. 1. Fig. 4

is a plan view of the parts of the device shown in Fig. 3 with certain parts. in section as indicated; at line' 44: on Fig. 3. Fig. 5 is a detail section taken as indicated at line 5'5 on Fig. 4:.

- Since the rotational speed of the so-called propeller shaft of a motor driven vehic'le uually bears a fixed relation to the speed of rotation of the road wheels, it is convenient and often preferable'to'connect a speed-indicating instrument directly to such propeller shaft. In the present instance thespeedometer, A, shown mounted on the dash tion of the propeller shaft is transmitted.

board,B, is provided with a jointed shaft formed of a vertical and a horizontal section, C and D, respectively, Operatively coni1ected by spiral gears at, E, and the rota.

to the speedometer, A, through a belt, F, passing over pulleys, G and H, which are, respectively, carried by the propeller shaft,

' J, and the transmitting device, 1K which is mounted on the frame, L, for positioning the fore-and-aft extending shaft, D, laterally with respect to the propeller shaft. Preferably the belt, F, is-of the Well known coiled wire type, thus being sufiiciently clastic and flexible to accommodate itself to variations in the position of the propeller shaft incident to the spring action of the 'plleys be of nearly equal diameters, but

since such a relation of sizes Would notsecure the necessary modification of the propeller shaft speed for use in the speedometer, A, there 1s provided in the supporting arm, K a housing, K", within which are journxled the speed-chariging gears, K and K", connected, respectively, to the shaft of the pulley, H, and to the shaft, D,.above mention'ed. As shown, the housing is provided with a journal bearing at K for the shaft of the gear, K", and the cover piece, K",is formed to furnish-an additional bearing for this shaft at, K and also a bearing for the shaft of the gear, K at K.- This cover piece may also be provided with a split socket, K", and clamp screw, K for securing a t1ibular housing for the'shaft, D, when one is provided. It Will be understood that the shafts, C, and D, may be replaced by a single flexible or jointed shaft of any well known construction extending from the socket, K", to the speedometer at, A, in which case, by virtu'e of the other drive connections from the propeller shaft, J, such flexible Shaft, L, need have but a single bend, as indicated 111- Fig. 6.

I claim:-

' 1. A device for the purpose indicated, comprising a brackt arm, a pulley and its shaft journaled therein, said shaft being provided with a gear, a cavity formed in the arm to accoinmodate said gear, a cover plate for Said cavity, a second gear in the cavity meshing with the first and having a shaft journaled in said cOver plate, said shaft befor transmitting motion, said cover plate having a bearing for the shaft which is journaled in the bracket arm, said shaft being xtendedbeyond the gear thefeon for I n testim0ny;whereofy I have l mpmato sel: entrane into such journal bearing in the my hztnd at'Ch1cago, Illmo1s, th1S 20 dny of cover plate, the cover plate being adapted J une, 1918.

(20 be applied. by movement longitudinally 1 v 1' of the two shafts for -ent'ering the gears LDXVARD-A' LJwOA' into 'mesh and the lst-mentioned sh ait into NVitnesses: the. over plate journal bearing.by the sam O. O. SAUTIREAU,

movement. STANHOIE IIUDSON.

Copies of this patent may be obtained. for fivje cents each, by addressing the COmmissioner cf Patents,

' Washington, D. C. 

